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Change in Earth's average global temperature over the past 1000 years showing that during the Medieval Warm Period (950-1100A.D.) temperatures were likely similar to the first part of the 20th century, climate cooled during the Little Ice Age (1350-1850), and has warmed dramatically in recent decades.
Click on image for full size Courtesy of NOAA

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The Medieval Warm Period

The Medieval Warm Period was a time of warm climate in Europe. The warmest part of the Medieval Warm Period was from about 950 until 1100 A.D. The warm climate overlaps with a time of high solar activity called the Medieval Maximum. The Medieval Warm Period occurred before the Little Ice Age, a time of cool climate in Europe and other places around the world. The graph on the left shows a reconstruction of average global temperatures over the past 1000 years with temperatures during the Medieval Warm Period similar to the first part of the 20th Century, cooler temperatures during the Little Ice Age, and dramatic warming in recent decades. The Medieval Warm Period was likely cooler than the past few decades.

According to some archaeologists, the Vikings may have been better able to explore and colonize many areas in Northern Europe while the climate was relatively warm during the Medieval Warm Period because there was less sea ice. They traveled by boats to Greenland among other places through seas that would later become blocked by sea ice during the Little Ice Age.

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